Microscopic model for the nonlinear behavior of high-k metal-insulator-metal capacitors

摘要

The achievement of sufficient capacitance-voltage linearity in metal-insulator-metal (MIM) capacitors with high permittivity (high-k) dielectrics is still a challenge, as the origin of the nonlinear behavior is still unclear. Based on fundamental physical mechanisms, such as electrostriction, Coulomb interaction between electrodes, and nonlinear optical effects, a microscopic model, which describes the nonlinearities in capacitance-voltage characteristics of high-k MIM capacitors, will be presented. The extended model, which includes stacked high-k dielectrics and interfacial layers, is able to predict the quadratic voltage capacitance coefficients as a function of the dielectric constant. The calculated coefficients are in suitable agreement with the experimental values of Al_2O_(3~-), Y_2O_(3~-), HfO_(2~-), and Pr_2Ti_2O_7-based MIM capacitors.